Just replaced the brake pads at all four corners on my 2004 LS430 with 58k miles. The rotors showed no perceptable wear and do not show any signs of warping, so I did not replace them. The pad replacement was very easy, due in large part to the non-floating caliper design Lexus uses. One thing I noticed with the OEM replacement pads is they are tapered, such that the pad material area that contacts the rotor is less when they are new and increases over time as the pads wear. That is odd, as it seems like braking performance would be less when the pads are new due to decreased pad contact area with the rotor as compared with later in pad life when the pads are worn down and more pad area is exposed to the rotor. I did not notice any reduced braking effectiveness after installing the new pads compared with the old pads which were worn about 80%. Just seemed strange - anybody know why the OEM pads are tapered? I've replaced brakes on many of my vehicles in the past and never noticed the pads being tapered.

 

I have not done a brake pad replacement but I've heard they are almost as easy as drop them in and you're done. Heck, I haven't even taken a tire off yet.

Maybe they're tapered to assist in sliding the pad into place, without the need to compress the caliper allowing free space for the pad to slide in?

 

More brake pad questions:

1) For those of you that did a DIY brake job, do you recommend replacing the anti-squeal shims? Service manual states "When replacing worn pads, the anti squeal shims must be replaced together with the pads."

2) Service manual mentions using "disc brake grease". Any recommendations for a specific brand?

3) After changing the pads, do you recommend bleeding the master cylinder and brake lines? Service manual states that after changing the pads, do the following steps:

FILL RESERVOIR WITH BRAKE FLUID (SEE PAGE 32−4)
BLEED MASTER CYLINDER (SEE PAGE 32−4)
BLEED BRAKE LINE (SEE PAGE 32−4)
BLEED BRAKE ACTUATOR (SEE PAGE 32−4)
CHECK BRAKE FLUID LEAKAGE
CHECK FLUID LEVEL IN RESERVOIR (SEE PAGE 32−4)

4) Are the steps in Q3 equivalent to a "brake fluid flush"?

Thanks in advance!

 

I have not replaced the pads on my LS yet, but when it comes time I will do the same that I've done with all my other vehicles:

1. clean and reuse the shims. They should be metal and why replace with new ones just to have shiney new ones. The old ones that fit will be just as good.

2. just anything from generic auto parts store that greese for high temp.

3. I have never bled the system after changing the pads. Unless you have an existing leak, or you developed a leak while changing, I would not bleed the system if the fluid still looks fresh. If it's brown, then I'd consider bleeding them since you have the wheels off.

4. pretty much.

 

I replaced the shims and pads together. The shims cost about the same price as the pads, per axle.

IIRC, the Toyota shims come with a pack of disc brake grease. The manual tells you where to put the grease. IIRC on my LX, I put the grease on the back side of the pad, then on both sides of the inner "mesh" looking shim, then on the inside of the inner shim. You do not need to bleed the brakes after changing pads unless you mistakingly loosened the brake hose! You will need to remove some fluid from the resevoir so it doesn't overflow when you push the pistons in.

No Q3 is not a brake flush. To flush, you need to bleed each caliper until the fluid runs clear. Start from the furthest wheel, usually the PS rear, then DS rear, PS front, DS front. Toyota calipers are easy to bleed, mostly because you don't have to remove the wheel to bleed them! On my LX and all Toyota trucks, you can slide underneath w/ a hose (I use 1/4" I.D. for Toyota trucks) and empty container and work the 10mm wrench while a buddy presses on the brake pedal. Make sure to check the resevoir every 10-15 pumps to ensure sufficient fluid (don't pump it dry!). The LX has a vacuum booster, so the master bleeds in the conventional way. You only can't bleed the ABS resevoir w/o the lexus tester. On Toyota trucks, they use the funky electric brake booster; FSM says to use the Lexus tester ($2700!) to bleed it.

 

So if you can't bleed the LS430 ABS system without the Lexus tester, how can you flush the brake fluid on your own? I read somewhere that you can connect a pin to something to emulate the same action as the Lexus tester.

Maybe I should just change the pads myself and then take the car in for the brake fluid flush? Anyone have any ideas what the dealership prices are for just a brake fluid flush?

 

I was quoted $125, so I went to a private shop and had it done for $87. It definitely is not rocket science. Had the rear end fluid changed for $57, dealer wanted $100. Shop around on the simple things, you can save quite a bit of money.

 

I did my pads and used the old shims,, once they were cleaned up I could not see any wear areas,, as for the calipers a good micrometer should be used to measure for wear and to assure they are still in the range specs,, eyeball checking is not recommended,,

it is advisable to have the brake system FULLY drained/flushed at least every five years,,

Derry

 

I assume you can jump the terminals (no $2700 tool required) and actuate the ABS pump to flush it. I don't know how to do it on the LS, but I do know how on the Supra and it is simple.

Another way, which will waste more fluid and take more time, but will work, is to "flush" the fluid in the rest of the system, then go out and put the car into ABS a few times to cycle new fluid in/old fluid out of the ABS pump, then do another flush of the system. Again, that works on other cars, so I ASSume it would on the LS.

That said, IMO the fluid in the sealed-from-moisture ABS pump should be in pretty good condition, so frankly I wouldn't really worry about it until it was about 10 years old. I doubt my car has ever been in ABS mode, so it's probably got the same exact fluid in the pump that came from the factory.

 

A quick recommendation on ABS master cylinder longevity I learned the hard way a few years ago. If you live in a climate where your ABS never kicks on, it is a good idea to make you car go into ABS braking mode approximately every other month or so to keep the ABS seals lubricated. In southern or desert climates where ABS rarely if ever turns on, the seals in the ABS tend to lose their lubrication, dry out, and potentially adhere to surfaces because they haven't moved/been actuated in so long. When they do finally move when ABS kicks on, they can tear which is death for a seal and an extremely expensive repair/replace.

So if you live in a dry warm climate, and are out in the rain or loose road surface and its been a while since ABS got a workout, briefly hit the brakes on a loose or slippery surface hard enough to feel the ABS kick in to lubricate and free up the seals. Don't go crazy and cause an accident however. And once every other month should be enough.